This project involves computer-based mathematical analysis, pattern recognition, and image processing in support of diagnostic activities in the Nuclear Medicine Department of the Clinical Center and collaborating institutes. Diverse applications include: computerized ECG-gated radionuclide ventriculography, myocardial perfusion scintigraphy, tagged monoclonal antibody studies, PET studies of the brain, and pulmonary ventilation- perfusion relationships. Technical developments include: evaluation of the use of personal computers in nuclear medicine imaging; the development of a new general purpose image processing facility for the Nuclear Medicine Department; and the development of methods to facilitate automated multimodality image registration of the head and other anatomy.